1. Field of the Invention
This invention relates to dicyclododecyl peroxydicarbonate having the following formula, which can be stored at room temperature for a long time and transported at room temperature. It is useful as a polymerization initiator for ethylenically unsaturated monomers and as a curing catalyst of unsaturated polyester resin compositions. ##STR2##
2. Description of the Prior Art
F. Strain discloses in U.S. Pat. No. 2,370,588 and Journal of American Chemical Society Vol. 72, 1254-1263 (1950) a process for preparing peroxydicarbonates including IPP (diisopropyl peroxydicarbonate), that they are useful as polymerization initiators which are active at a low temperature in the polymerization of ethylenically unsaturated monomers such as ethylene, styrene, methyl methacrylate, vinyl chloride and the like, and further, dicyclohexyl peroxydicarbonate is mentioned as a dialkyl peroxydicarbonate having cycloalkyl groups. The described peroxydicarbonates have the disadvantage in that they must be cooled during use or storage.
Japanese patent publication No.SHO43-17572 discloses that 4-substituted dicyclohexyl peroxydicarbonates, for example, di-(4-tertiary butylcyclonexyl) peroxydicarbonate is stable at room temperature and accordingly it does not need to be frozen or stabilized during transportation and storage.
Japanese patent publication No.SHO47-3970 also discloses that di-(cis - 3,3,5 - trimethylcyclohexyl) peroxydicarbonate is stable at room temperature.
Further, Japanese Patent Publication No.SHO47-3971 discloses that di-(bicycloalkyl) peroxydicarbonates such as dibornyl peroxydicarbonate are stable at room temperature.
It is an object of the present invention to provide a non-substituted dicycloalkyl peroxydicarbonate which needs no cooling during handling or during storage.
It is another object of the present invention to provide a non-substituted dicycloalkyl peroxydicarbonate which possesses better solubility in organic solvents better the compability with unsaturated polyester resins in comparison with the commercially available peroxydicarbonates and which can cure unsaturated polyester resin compositions easily.
It is still another object of the present invention to provide a non-substituted dicycloalkyl peroxydicarbonate which is high in polymerization activity when it is used as a polymerization initiator.
It is another object of the present invention to provide a non-substituted cycloalkyl peroxydicarbonate which gives good characteristics to the obtained polymers.
The inventors completed this invention on the basis of the discovery that dicyclododecyl peroxydicarbonate, a novel compound, can be produced by reacting cyclodecyl chloroformate with hydrogen peroxide in the presence an alkali and that the thus obtained compound is stable at room temperature so that it can be stored for a long time without spontaneous combustion, and that the said compound has good solubility in organic solvents and good compatibility with unsaturated polyester resins, and is useful as a polymerization initiator possessing very high polymerization activity.
The said novel compound, of which the melting point is 76.degree.-78.degree. C. (decomposes at 77.degree.-78.degree. C.), is solid at room temperature.
This compound loses its assay only 6.6% when it is kept at a temperature of 30.degree. C. for 3 weeks and only 7.0% when it is kept at 40.degree. C. for a week.
The characteristic absorptions in the infrared spectrum of this compound were observed at 1790 cm.sup.-1 (.nu. c=o) and 895 cm.sup.-1 (.nu. o - o) corresonding to the characteristic absorptions of the peroxycarbonyl group.
In the nuclear magnetic resonance spectrum of this compound (solvent; CCl.sub.4, standard material;tetramethylsilane), an absorption band of methylene protons was observed at 1.39 of .delta. (singlet), an absorption band of 8 .beta.-methylene protons at 1.62-2.38 of .delta. (multiplet) and an absorption band of 2 .alpha.-methylene protons at 4.76-5.12 of .delta. (multiplet).
Notwithstanding that dicyclododecyl peroxydicarbonate of the present invention is a solid crystal, the said compound has the advantage in that the solubilities thereof in organic solvents are so high that it can be dissolved in a small quantity of organic solvent when it is used in the form of a solution in the organic solvent.
Further it has another advantage in that when it is used as a curing catalyst for unsaturated polyester resins, the time for mixing the resins and the catalyst can be shortened, in comparison with a commercially available peroxydicarbonate that is stable at room temperature.